The primary objective of the Animal Hypoxia (Core C) is to provide standardized chronic exposures of sustained and intermittent hypoxia and/or hypercapnia to flies and mice used by all of the Projects, and to characterize the essential respiratory and cardiovascular phenotypes in the different species, genotypes, and exposures studied by the individual Projects. Standardizing exposure is vital for integrating the findings between the different Projects and optimizing data sharing. Centralizing this also insures quality control and dissemination of any results from individual Projects suggesting that the exposure protocols should be adjusted. Importantly, this centralization also conserves animals and resources to maximize the budget and animal sacrifice. Behavioral measurements are not included in this revised proposal but the larger Biospherix chambers, which house multiple animals and cages will be used for all chronic exposures to insure identical social interactions and conditioning. Phenotyping mice in the core also minimizes the cost and maximizes the information individual animal models in terms of the basic metabolic, respiratory and cardiovascular physiology that is necessary for all of the individual Projects. Given the challenges of maintaining disease free-breeding colonies for multiple lines of transgenic mice, it is most efficient and cost effective to make non-invasive and non-terminal descriptive measurements within a physiology core facility before distributing chronically exposed animals to individual laboratories for the actual experiments. Physiological data will be uploaded to a database developed with Systems Biology Core B for all the investigators to use so the projects can focus on the biology. Training in the physiological techniques used to phenotype the animals will also be provided by Core C to predoctoral students and postdoctoral fellows working in the individual Projects.